Tory Prime Minister David Cameron, Labour's Harriet Harman, Lib Dem leader Tim Farron and Green Party leader Natalie Bennet have shared a platform to make the case to Remain in the European Union.
But it's not the first example of cross-party harmony in either the EU referendum or recent history. Here are some of our favourite pictures.
- 1Cable, Osborne and Balls, 2016Stefan Rousseau/PA Wire
- 2Heseltine, Blair and Clarke, 2001Stefan Rousseau/PA Archive
- 3Farron, Cameron and Harman, 2016WPA Pool via Getty Images
- 4Major, Blair and Brown, 2012Stefan Rousseau/PA Archive
- 5Khan and Cameron, 2016Yui Mok/PA Archive
- 6Davidson, Sturgeon and Dugdale, 2016Andrew Milligan/PA Wire
- 7Ashdown, Cameron and Kinnock, 2016Stefan Rousseau/PA Wire
- 8Wood, Sturgeon and Farage, 2015Stefan Rousseau/PA Archive
- 9Miliband, Clegg and Cameron, 2014LEFTERIS PITARAKIS via Getty Images
- 10Cameron, Osborne and Harman, 2015Dan Kitwood via Getty Images
- 11Brown, Cameron and Clegg, 2010Handout via Getty Images
- 12Major, Ashdown and Blair, 1995ASSOCIATED PRESS